Imatinib, a tyrosine kinase receptor inhibitor (PDGFR α and β, DDR, c-KIT, CSF1R, ABL) approved for the treatment of chronic myeloid leukemia, had proven to reverse PAH in animal models and suggested to be clinically and hemodynamically effective as adjunctive treatment of patients with PAH in case reports and a phase-2 trial [98,99,100]. Here, PDGFRB is linked to pulmonary arterial hypertension.